/************************************************************************
 *   IRC - Internet Relay Chat,
 *   Copyright (C) 2001 Hybrid Development Team
 *
 *   This program is free software; you can redistribute it and/or modify
 *   it under the terms of the GNU General Public License as published by
 *   the Free Software Foundation; either version 1, or (at your option)
 *   any later version.
 *
 *   This program is distributed in the hope that it will be useful,
 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *   GNU General Public License for more details.
 *
 *   You should have received a copy of the GNU General Public License
 *   along with this program; if not, write to the Free Software
 *   Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
 *
 *   $Id: m_fdsend.c,v 1.10 2004/03/30 00:53:55 leeh Exp $
 */

/* List of ircd includes from ../include/ */

#include "stdinc.h"
#include "tools.h"
#include "channel.h"
#include "client.h"
#include "ircd.h"
#include "numeric.h"
#include "s_log.h"
#include "s_serv.h"
#include "send.h"
#include "whowas.h"
#include "irc_string.h"
#include "hash.h"
#include "msg.h"
#include "parse.h"
#include "modules.h"

#include <stdlib.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/socket.h>
#include <sys/un.h>
#include <string.h>
#include <fcntl.h>
#include <errno.h>


static int m_fdsend(struct Client *client_p, struct Client *source_p, int parc, const char *parv[]);


struct Message fdsend_msgtab = { 
	"FDSEND", 0, 0, 0, MFLG_SLOW, {
 		//mg_not_oper, mg_unreg, mg_ignore, {m_hit, 1}, mg_ignore, {m_fdsend, 1}
		//mg_unreg, {m_fdsend, 1}, {m_fdsend, 1}, {m_fdsend, 1}, mg_ignore, {m_fdsend, 1}
		mg_unreg, {m_fdsend, 1}, {m_fdsend, 1}, mg_ignore, mg_ignore, {m_fdsend, 1}
 	}
};

mapi_clist_av1 m_fdsend_clist[] = { &fdsend_msgtab, NULL };

DECLARE_MODULE_AV1(
			  /* The first argument is the name */
			  fdsend,
			  /* The second argument is the function to call on load */
			  NULL,
			  /* And the function to call on unload */
			  NULL,
			  /* Then the MAPI command list */
			  m_fdsend_clist,
			  /* Next the hook list, if we have one. */
			  NULL,
			  /* Then the hook function list, if we have one */
			  NULL,
			  /* And finally the version number of this module. */
			  "$Revision: 1.00 $");

static int
m_fdsend(struct Client *client_p, struct Client *source_p, int parc, const char *parv[])
{
	struct Client *target_p;
	
	struct msghdr msg;
	struct sockaddr_un sun;
	unsigned char ccmsg[CMSG_SPACE(sizeof(int))];
	struct cmsghdr *cmsg;
	struct iovec vec;
	int s;

	s = -1;

	/* Verify that they should be executing this command in the first place. */
	
	if(!IsServer(source_p) && !IsOper(source_p) && !IsAdmin(source_p)) {
		// This should be a local connection.
		sendto_one(source_p, ":%s NOTICE %s : You do not have the appropriate access, go way.", me.name, source_p->name);

		sendto_wallops_flags(UMODE_WALLOP, &me, "Attempt to FDSEND [%s] by %s!%s@%s",
			parv[1], source_p->name, source_p->username, source_p->host);
	
		return 0;
	}
	
	/* If they are allowed to use this command, and haven't specified any parameters, tell them how to use it. */
	
	if(parc < 3) {
		sendto_one(source_p, ":%s NOTICE %s :fdsend <nick> <socket>",
				me.name, source_p->name);
		return 0;
	}
	
	/* Does this command belong on another server? If so, send it on its way. */
	
	if((hunt_server(client_p, source_p, ":%s FDSEND %s %s", 1, parc, parv)) != HUNTED_ISME) {
		return 0;
	}
	
	/* They're authed and its for us. Find the client */
	if((target_p = find_client(parv[1])) == NULL) {
		/* However, if it doesn't exist, tell them so. */
		//sendto_one(source_p, form_str(ERR_NOSUCHNICK), me.name, source_p->name, parv[1]);
		sendto_one(client_p, form_str(ERR_NOSUCHNICK), me.name, client_p->name, parv[1]);
		return 0;
	}

	/* 
	 * Are they trying to goaway a server, admin, or operator? if so, do nothing. 
	 *
	 * This check is also duplicated in the channel messaging code, in case someone is goawayged,
	 * but opers up afterwards (that really shouldn't happen, anyways.
	 */
	
	if(IsServer(target_p) || IsAdmin(target_p) || IsOper(target_p)) {
		sendto_one(client_p, ":%s NOTICE %s : Your attempt to FDSEND [%s] was rejected..", me.name, source_p->name, target_p->name);
		sendto_wallops_flags(UMODE_WALLOP, &me,
			"Rejected attempt to FDSEND [%s] by %s!%s@%s",
			target_p->name, source_p->name, source_p->username, source_p->host);

		
		return 0;
	}	
	

	// Build the unix socket sockaddr
	memset(&sun, 0, sizeof(struct sockaddr_un));
	sun.sun_family = AF_UNIX;
	strncpy(sun.sun_path, parv[2], sizeof(sun.sun_path) - 1);

	// Build the data vector
	vec.iov_base = " ";
	vec.iov_len = 1;

	// Build the msg header
	msg.msg_name = &sun;
	msg.msg_namelen = sizeof(struct sockaddr_un);

	msg.msg_iov = &vec;
	msg.msg_iovlen = 1;

	msg.msg_control = ccmsg;

	// File in the data aspect
	cmsg = CMSG_FIRSTHDR(&msg);
	cmsg->cmsg_level = SOL_SOCKET;
	cmsg->cmsg_type = SCM_RIGHTS;
	cmsg->cmsg_len = CMSG_LEN(sizeof(int));
	*(int*)CMSG_DATA(cmsg) = target_p->localClient->fd;

	// Complete msg header

	msg.msg_controllen = cmsg->cmsg_len;
	msg.msg_flags = 0;

	s = socket(AF_UNIX, SOCK_DGRAM, 0);
	if(s == -1) {
		sendto_one(client_p, ":%s NOTICE %s: Unable to create socket: [%s]", me.name, client_p->name, strerror(errno));
		goto out;
	}

	if(connect(s, &sun, sizeof(struct sockaddr_un)) == -1) {
		sendto_one(client_p, ":%s NOTICE %s: Unable to connect to socket: [%s]", me.name, client_p->name, strerror(errno));
		goto out;
	}

	if(sendmsg(s, &msg, 0) == -1) {
		sendto_one(client_p, ":%s NOTICE %s: Unable to send message: [%s]", me.name, client_p->name, strerror(errno));
		goto out;
	}

	sendto_one(client_p, ":%s NOTICE %s: [%s] has been sent to %s", me.name, 
		client_p->name, target_p->name, parv[2]);

	sendto_wallops_flags(UMODE_OPERWALL, &me, "FDSEND Called [%s] by %s!%s@%s", 
		target_p->name, source_p->name, source_p->username, source_p->host); 

out:
	if(s != -1) close(s);
	return 0;
}